Oh there is some and it includes your laptop computer.
Cold Cathode fluorescent Lamp construction Flourescentlamps.JPG (29313 bytes) Cold Cathode fluorescent Lamp Typical operational specifications for a 14.1" LCD Backlight (CCFL) DIAMETER (mm) 2 LAMP VOLTAGE VL(Vrms) 810 LENGTH (mm) 293 LAMP WATTS (@5mArms) 3.7 STARTING VOLTAGE (Typ.Vrms) 1820 INTENSITY (Cd./m2) 38,000 Life Hrs. (Typ.) 20,000 Cold Cathode fluorescent Lamp construction typically includes a hollow glass cylinder which has been coated on the inside with a phosphor material Composed of rare earth elements such as zinc silicate and various types of halophosphates. The tube is then sealed at both ends, each of which also contains a gettered, mercury-dispensing electrode and an iron-nickel cathode connected to copper sheathed iron alloy leads. Lamps normally contain 2 to 10 milligrams of mercury, and a mixture of gasses such as argon and neon. When high voltage is applied to the electrodes, ultraviolet energy at 254hm is produced as the mercury and the internal gasses are ionized. The resulting ultraviolet energy from, the mercury discharge stimulates the phosphor lining inside the Iamp, producing visible light out-put in the 380 to 780nm range, also known as the photopic region. The most widely used CCFL lamps utilize phosphors specially compounded for good color rendering in illuminating liquid crystal displays (LCDs). They are referred to as triphosphor RGB lamps, producing bright white light, utilizing a combination of red, green and blue phosphors. Light output for Iamp phosphors is measured in degrees Kelvin (OK). A typical RGB fluorescent Iamp is rated at 5600 degrees Kelvin, which approximates daylight. The cooler blue the lamp color the higher Kelvin rating. Inversely a lower Kelvin rating produces a warmer the lamp color Lower Kelvin ratings have a warm (red/yellow) appearance. Higher Kelvin ratings are typically blue-white. Most computer Liquid Crystal Display (LCD) panels are lit with built-in fluorescent tubes above, beside and sometimes behind the LCD. A white diffusion panel behind the LCD redirects and scatters the light evenly to ensure a uniform display. This is known as a backlight. A fluorescent light is most often a long straight glass tube that produces white light. Inside the glass tube there is a low-pressure mercury vapor. When ionized, mercury vapor emits ultraviolet light. Human eyes are not sensitive to ultraviolet light (although human skin is). The inside of a fluorescent light is coated with phosphor. Phosphor is a substance that can accept energy in one form and emit the energy in the form of visible light. For example, energy from a high-speed electron in a TV tube is absorbed by the phosphors that make up the pixels. The light we see from a fluorescent tube is the light given off by the phosphor coating the inside of the tube. The phosphor fluoresces when energized, hence the name. A typical laptop display uses a tiny Cold Cathode Fluorescent Lamp (CCFL) for the backlight. One of these small tubes is able to provide a bright white light source that can be diffused by the panel behind the LCD. In addition to providing ample light, CCFLs do not rise far above the ambient temperature. This makes them ideal for LCD panels since the light source is in close proximity to other components that could be ruined by excessive heat. One amazing thing about these lamps is their incredible size. They are very thin and the board that drives the lamp is very small as well. However, it is not that hard to break them, which is why your display may go dark if you drop your laptop. Fluorescent Light Advantage of LCD technology, behind the liquid crystals (which the "L" and "C" letters stand for), there was a source of light. This happened to be the same fluorescent light technology which, I knew, was not recommended for use as the only light source in offices. So, if there was something less than ideal about using it too much in an office, how came nobody mentioned this in relation with the fact that LCD display users stare at such lights all day? Checking things like the refresh rates and the frequency peaks of a source of fluorescent light is not normally done with CRT displays, and does not naturally cross one's mind when thinking of liquid crystal displays. The fluorescent light is a separate component from the LCD display, and is never mentioned as part of the final "LCD display" product. Two aspects of fluorescent lighting are in my opinion worth mentioning. * Fluorescent lights, like other types of lighting technology, including the sun, have their own frequency spectrum, with peaks at certain bandwidths. * Unlike the sun (and other lighting technologies), fluorescent lights are not stable, but rather, they are pulsing, i.e. they go on and off several times per second. CCFL,s operate at several hundreds or thousands of Hertz. I know that many experts are claiming that we cannot perceive certain higher refresh rates, but when I consider that the sunlight does not go on and off all the time, but rather it is "always on", I can't avoid thinking that everything else is not as "natural". The negative effects of 100% fluorescent room lighting have been known and studied for some time, and thinking about it from this perspective I would find it logical that directly staring at a source of fluorescent light can be just as bad, if not worse. I know that many people have problems with the energy-efficient fluorescent room illumination in general, and prefer the traditional light bulb, which I believe has a wider frequency spectrum. The incandescent filament of a light bulb probably also generates a more stable light than the fluorescent substrate under the intermittent pulses of electrons. Assuming that fluorescent light is a bit like the scan lines of a television, i.e. it turns on and off all the time, but our eyes and nervous system make us perceive it as a persistent light, I cannot understand how some publications that praise LCD displays ignore this similarity with what is possibly the most negative aspect of CRT displays. Even if you don't normally perceive the flickering of your display or TV, if you point your eyes upwards, you may be able to discern some flickering in the lower part of the visual region (the peripheral area is more sensitive to flickering). I am sure that there is a range of frequencies, which may or may not include the refresh rates normally used for fluorescent light, which cannot be perceived by the average person, but which can cause discomfort in the longer term. Fluorescent light is a factor or co-factor in LCD,s because the spectral distribution of the light is not what evolution trained us to live with, or because a pulsating source of light is used for the background laptop illumination. Dale Leavens, Cochrane Ontario Canada [EMAIL PROTECTED] Skype DaleLeavens Come and meet Aurora, Nakita and Nanook at our polar bear habitat. ----- Original Message ----- From: David Sexton To: [email protected] Sent: Sunday, September 30, 2007 12:43 AM Subject: Re: [BlindHandyMan] WOW, FYI, News Release: Bulbs To Save Energy Are Very Dangerous To Children Correct me if I'm wrong, but I seriously don't believe there is mercury in floressent bulbs. You need a floressent gas like neon... ----- Original Message ----- From: Max Robinson To: [email protected] Sent: Saturday, September 29, 2007 11:36 PM Subject: Re: [BlindHandyMan] WOW, FYI, News Release: Bulbs To Save Energy Are Very Dangerous To Children They are written by weak minded people who exaggerate the danger by a factor of 1000. Mercury vapor will dissipate within a few minutes. How often do light bulbs get broken. I doubt if we have broken 5 bulbs in 36 years of living here. Regards. Max. K 4 O D S. Email: [EMAIL PROTECTED] Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Music site: http://www.maxsmusicplace.com To subscribe to the fun with tubes group send an email to, [EMAIL PROTECTED] ----- Original Message ----- From: "Dale Leavens" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, September 29, 2007 11:05 PM Subject: Re: [BlindHandyMan] WOW, FYI, News Release: Bulbs To Save Energy Are Very Dangerous To Children > Could be but why do these messages always come written with incorrect > grammar and spelling? > > It is a conspiracy to retard the language skills of our children, the > generation we will depend on to keep what ever sort of lights burning into > the future. > > Dale Leavens, Cochrane Ontario Canada > [EMAIL PROTECTED] > Skype DaleLeavens > Come and meet Aurora, Nakita and Nanook at our polar bear habitat. > > > ----- Original Message ----- > From: Barbara > To: Undisclosed-Recipient:; > Sent: Saturday, September 29, 2007 9:06 PM > Subject: [BlindHandyMan] WOW, FYI, News Release: Bulbs To Save Energy Are > Very Dangerous To Children > > > Bulbs To Save Energy Are Very Dangerous To Children > > > September 30, 2007 > > Environmentally Friendly Bulbs To Save Energy Are Very Dangerous To > Children > By Thomas M. Dutkiewicz > > Forestville, CT - Why is the media acts so surprised that these new bulbs > to save energy are dangerous? To say that these bulbs are environmentally > friendly is an oxymoron. They are anything but friendly . . . they are > dangerous to the environment and to all children. > > They are florescence bulbs and all florescence bulbs contain dangerous > Mercury Vapor which is more dangerous than mercury liquid. For decades > they have been putting mercury vapor in the bulbs. That's what make them > work. > > Mercury in a liquid form can be seen and it balls up which is easier to > clean up. Mercury vapor on the other hand can not be seen nor can it be > detected by home owners. You need a special air monitoring device that > detects the presences of mercury vapor along the floor. You will not find > it in your breathing zone. > > The specific gravity of mercury vapor is heavier than air and will settle > into your rugs and stay there. So next time you break one of these bulbs > in your home, you are exposing your children to mercury vapor. So remember > this when you place your baby or children on the floor. > > You need a special absorption pellet that absorbs mercury vapor on the > floor. Then the hazmat team must vacuum it up and dispose of the pellet as > a contaminated material. You then go in with monitoring equipment to see > if there is any residual mercury left and if there is, you repeat the > process. > > Every single florescence bulb in our schools, lunch rooms, grocery stores > contain mercury vapor. The mercury vapor is dangerous to all humans > especially children. Business should not be throwing florescence bulbs > away in dumpsters which then ends up in our water systems. > > What's even more deadlier is all of the older ballasts that are running > these florescence bulbs, they contain Polychlorinated Biphenyl's or PCB's. > In business renovations these contaminated ballasts are thrown out which > contain liquid PCB's which also gets into our water system. > > Home owners now have treat these bulbs as a hazardous material as defined > by the EPA and the DOT and dispose of them properly. The cost of disposal > will over shadow the cost savings. A couple of manufactures do print this > mercury warning on the packaging but no one ever reads the packaging of a > light bulb. > > The undersign has been in the hazardous waste, remediation and > transportation business for many years. He has cleaned up mercury vapor as > well as other numerous spills of various kinds. > > > Thomas M. Dutkiewicz > P.O. Box 9775 > Forestville, CT 06011-9775 > 860-833-4127 > > > > > > [Non-text portions of this message have been removed] > > > > > > [Non-text portions of this message have been removed] > > > > To listen to the show archives go to link > http://acbradio.org/handyman.html > or > ftp://ftp.acbradio.org/acbradio-archives/handyman/ > > The Pod Cast address for the Blind Handy Man Show is. > http://www.acbradio.org/news/xml/podcast.php?pgm=saturday > > Visit The Blind Handy Man Files Page To Review Contributions From Various > List Members At The Following address: > http://www.jaws-users.com/handyman/ > > Visit the archives page at the following address > http://www.mail-archive.com/[email protected]/ > > If you would like to join the Blind Computing list, then visit the > following address for more information: > http://jaws-users.com/mailman/listinfo/blind-computing_jaws-users.com > > For a complete list of email commands pertaining to the Blind Handy Man > list just send a blank message to: > [EMAIL PROTECTED] > Yahoo! Groups Links > > > > > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.5.488 / Virus Database: 269.13.35/1039 - Release Date: > 9/29/2007 9:46 PM > [Non-text portions of this message have been removed] [Non-text portions of this message have been removed]
